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Multisystem inflammatory syndrome in children during the COVID-19 waves: data from the Juvenile Inflammatory
Robin Kechiche1, Charlotte Borocco1, Fanny Bajolle2
1Department of Pediatric Rheumatology, Reference Centre for Autoinflammatory Diseases and Amyloidosis (CEREMAIA), Bicêtre University Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris-Saclay University, Le Kremlin-Bicêtre, France.
Insights
Multisystem inflammatory syndrome in children (MIS-C) cases became less severe over three COVID-19 waves, with decreased symptoms and inflammation. Improved management, including increased corticosteroid use, contributed to better outcomes in children.
Area of Science:
- Pediatric Rheumatology and Infectious Diseases
- Public Health and Epidemiology
- Critical Care Medicine
Background:
- Multisystem inflammatory syndrome in children (MIS-C) emerged as a significant concern during the COVID-19 pandemic.
- Understanding the evolving clinical presentation and management of MIS-C is crucial for pediatric healthcare providers.
- The initial waves of the pandemic presented unique challenges in diagnosing and treating this novel condition.
Purpose of the Study:
- To delineate the diagnostic trajectory of MIS-C in children and adolescents.
- To characterize the clinical and biological features of MIS-C across successive COVID-19 waves.
- To evaluate treatment strategies and their impact on patient outcomes during the pandemic.
Main Methods:
- Retrospective analysis of 136 patients diagnosed with MIS-C within the Juvenile Inflammatory Rheumatism (JIR) cohort.
- Data collection spanned from March 2020 to June 2021, encompassing the first three COVID-19 waves.
- Comparative analysis of patient data between the first wave and subsequent waves (two and three).
Main Results:
- A decrease in the median age of affected children was observed across waves.
- Later waves showed reduced incidence of diarrhea, respiratory distress, and myocarditis, alongside diminished inflammatory markers (e.g., C-reactive protein, neutrophil count).
- Treatment evolved, with increased corticosteroid use and decreased need for ventilation support and inotropic agents; hospitalization duration and ICU admissions also reduced.
Conclusions:
- The study indicates a less severe disease course for MIS-C in the JIR cohort over time.
- Increased utilization of corticosteroids and potentially evolving SARS-CoV-2 variants may explain the observed improvements.
- These findings highlight the dynamic nature of MIS-C and the impact of adaptive clinical management strategies.
Introduction:
Multisystem inflammatory syndrome in children (MIS-C) is a new condition that first appeared in children and adolescents during the COVID-19 pandemic. We aimed to describe the diagnostic course, clinical and biological manifestations, and treatment of MIS-C during the first three COVID-19 waves.
Methods:
We extracted patient data from the Juvenile Inflammatory Rheumatism (JIR) cohort. We analyzed data for patients meeting the World Health Organization diagnostic criteria for MIS-C from the start of the COVID-19 pandemic from March 2020 to June 30, 2021. We then compared data for patients in wave one to those in waves two and three.
Results:
We identified 136 patients with MIS-C. The median age decreased but not significantly during the waves, from 9.9 years to 7.3 years (p = 0.105). Boys represented 52.2% (n = 71) of patients, and 46% (n = 41) of patients originated from sub-Saharan Africa (p < 0.001). Patients presented less diarrhea (p = 0.004), respiratory distress (p < 0.001), and myocarditis (p < 0.001) with progressive waves. Biological inflammation also decreased, namely, C-reactive protein level (p < 0.001), neutrophil count (p = 0.004), and albumin level (p < 0.001). Patients received more corticosteroids (p < 0.001) and required less ventilation support (p < 0.01) and less inotrope treatment (p < 0.001) in the later waves. The duration of hospitalization gradually decreased (p < 0.001), as did critical care unit admissions (p = 0.002).
Conclusion:
Over the three COVID-19 waves, with a change in the management of MIS-C, children in the JIR cohort in France showed a less severe disease course, in particular, a greater use of corticosteroids. This observation may reflect the impact of both improved management and different SARS-CoV-2 variant.
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